Update changelog for 2020.2.0 preview release#2481

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rjmholt merged 3 commits intoPowerShell:masterfrom

rjmholt:changelog-2020.2.0

Feb 19, 2020

Commits on Feb 19, 2020

Update preview changelog
Rob Holt
committed
Update package version
Rob Holt
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Add new changelog items
Rob Holt
committed